In a laser cladding process, a laser beam melts a powder and also the surface of a substrate, and the two molten materials combine to form a coating upon solidifying. The coatings can have improved wear and corrosion resistance compared to the substrate, or the process can be used to rebuild worn or eroded surfaces using powder of the same material as the substrate.
With known powder delivery arrangements, the efficiency of laser cladding can vary substantially with the orientation of the laser delivery head and, hence, the direction in which the laser beam is delivered. When the delivery head is oriented other than in the down vertical direction for laser delivery, an uneven distribution of powder usually occurs. This is due to the influence of gravity, which is evident from there being more powder distributed to the lower side of the laser delivery head.
The present invention seeks to provide an improved powder delivery nozzle for a laser cladding laser delivery head, and a laser delivery head having the improved nozzle, which enables greater freedom to operate more efficiently in orientations other than the down vertical direction.